Heretofore, various multi-winding electronic components have been proposed as electronic components used for noise reduction, antennas, choke coils, and impedance matching circuits. The multi-winding electronic components are called coil components that have structures in which coils are wound around winding cores and electrify to produce magnetic fluxes.
For example, a coil component described in Japanese Unexamined Patent Application Publication No. 2005-327876 (hereinafter, “PTL 1”) (see, paragraphs 0029 to 0032, 0040, and 0041, FIG. 4, and so on) includes a core that is made of ferrite and that includes a winding core and collars provided at both ends of the winding core. Nickel films serving as electrodes are formed on the collars by an electroless deposition method. A lead wire made of a conductive material is, for example, doubly wound around the winding core and the ends of the lead wire are subjected to thermocompression bonding to the electrodes formed on the collars.
A lead wire is wound, for example, in the following manner in another coil component in related art, as shown in FIGS. 7 to 10.
In a coil component 21 shown in FIG. 7, an end 23a at which winding of a lead wire 22 is started is wired on an electrode 25a formed on one collar 24a, among the collar 24a and a collar 24b formed at both ends of a winding core 24, and the lead wire 22 is then wound around the winding core 24 toward the other collar 24b to form a bottom layer part 28. After the lead wire 22 is wound by a certain number of turns, the lead wire 22 is folded back in a manner shown in FIG. 8 and the lead wire 22 is wound over the bottom layer part 28 by a certain number of turns in a manner shown in FIG. 9 to form an upper layer part 29.
Then, the lead wire 22 is folded back toward an electrode 25b formed on the collar 24b at a certain position in a manner shown in FIG. 10, an end 23b of the lead wire 22 is wired on the electrode 25b while being pulled, and the lead wire 22 is subjected to the thermocompression bonding to the electrode 25a and the electrode 25b. 